Question

如何用matlab训练BP神经网络？

初学者，还摸不着头绪，愿多多指点。没啥财富可以感谢，希望不吝赐教！

Answer 1

net = newff(PR,[S1 S2...SNl],{TF1 TF2...TFNl},BTF,BLF,PF)

newff(PR,[S1 S2...SNl],{TF1 TF2...TFNl},BTF,BLF,PF) takes,
PR - Rx2 matrix of min and max values for R input elements.
Si - Size of ith layer, for Nl layers.
TFi - Transfer function of ith layer, default = 'tansig'.
BTF - Backprop network training function, default = 'trainlm'.
BLF - Backprop weight/bias learning function, default = 'learngdm'.
PF - Performance function, default = 'mse'.
然后train一下就可以了，具体其他参数查阅相关文档，一般有前四个参数就够了。
看一个简单的例子：
有两个向量或者矩阵，pn和tn：
net=newff(minmax(pn),[3,1],{'tansig','purelin'},'trainlm');
net.trainParam.epochs=1000;
net.trainParam.goal =1e-5;
net=train(net,pn,tn);
照葫芦画瓢就行，具体参数意义就不说了，自己查阅matlab帮助。

Answer 2

加一句net.trainParam.show＝1